“Observe, in this connection, the widespread phenomenon of men who are old by the time they are thirty. These are men who, having in effect concluded that they have ‘thought enough,’ drift on the diminishing momentum of their past effort—and wonder what happened to their fire and energy, and why they are dimly anxious, and why their existence seems so desolately impoverished, and why they feel themselves sinking into some nameless abyss—and never identify the fact that, in abandoning the will to think, one abandons the will to live.”